Method Detail

getInstance

Gets the instance which provides the functionality for BeanUtils.
This is a pseudo-singleton - an single instance is provided per (thread) context classloader.
This mechanism provides isolation for web apps deployed in the same container.

Returns:

The (pseudo-singleton) BeanUtils bean instance

setInstance

Sets the instance which provides the functionality for BeanUtils.
This is a pseudo-singleton - an single instance is provided per (thread) context classloader.
This mechanism provides isolation for web apps deployed in the same container.

copyProperties

Copy property values from the origin bean to the destination bean
for all cases where the property names are the same. For each
property, a conversion is attempted as necessary. All combinations of
standard JavaBeans and DynaBeans as origin and destination are
supported. Properties that exist in the origin bean, but do not exist
in the destination bean (or are read-only in the destination bean) are
silently ignored.

If the origin "bean" is actually a Map, it is assumed
to contain String-valued simple property names as the keys, pointing at
the corresponding property values that will be converted (if necessary)
and set in the destination bean. Note that this method
is intended to perform a "shallow copy" of the properties and so complex
properties (for example, nested ones) will not be copied.

This method differs from populate(), which
was primarily designed for populating JavaBeans from the map of request
parameters retrieved on an HTTP request, is that no scalar->indexed
or indexed->scalar manipulations are performed. If the origin property
is indexed, the destination property must be also.

If you know that no type conversions are required, the
copyProperties() method in PropertyUtils will
execute faster than this method.

FIXME - Indexed and mapped properties that do not
have getter and setter methods for the underlying array or Map are not
copied by this method.

copyProperty

Copy the specified property value to the specified destination bean,
performing any type conversion that is required. If the specified
bean does not have a property of the specified name, or the property
is read only on the destination bean, return without
doing anything. If you have custom destination property types, register
Converters for them by calling the register()
method of ConvertUtils.

IMPLEMENTATION RESTRICTIONS:

Does not support destination properties that are indexed,
but only an indexed setter (as opposed to an array setter)
is available.

Does not support destination properties that are mapped,
but only a keyed setter (as opposed to a Map setter)
is available.

The desired property type of a mapped setter cannot be
determined (since Maps support any data type), so no conversion
will be performed.

describe

Return the entire set of properties for which the specified bean
provides a read method. This map contains the to String
converted property values for all properties for which a read method
is provided (i.e. where the getReadMethod() returns non-null).

This map can be fed back to a call to
BeanUtils.populate() to reconsitute the same set of
properties, modulo differences for read-only and write-only
properties, but only if there are no indexed properties.

Warning: if any of the bean property implementations
contain (directly or indirectly) a call to this method then
a stack overflow may result. For example:

getIndexedProperty

Return the value of the specified indexed property of the specified
bean, as a String. The zero-relative index of the
required value must be included (in square brackets) as a suffix to
the property name, or IllegalArgumentException will be
thrown.

getMappedProperty

Return the value of the specified indexed property of the specified
bean, as a String. The String-valued key of the required value
must be included (in parentheses) as a suffix to
the property name, or IllegalArgumentException will be
thrown.

populate

Populate the JavaBeans properties of the specified bean, based on
the specified name/value pairs. This method uses Java reflection APIs
to identify corresponding "property setter" method names, and deals
with setter arguments of type String, boolean,
int, long, float, and
double. In addition, array setters for these types (or the
corresponding primitive types) can also be identified.

The particular setter method to be called for each property is
determined using the usual JavaBeans introspection mechanisms. Thus,
you may identify custom setter methods using a BeanInfo class that is
associated with the class of the bean itself. If no such BeanInfo
class is available, the standard method name conversion ("set" plus
the capitalized name of the property in question) is used.

NOTE: It is contrary to the JavaBeans Specification
to have more than one setter method (with different argument
signatures) for the same property.

WARNING - The logic of this method is customized
for extracting String-based request parameters from an HTTP request.
It is probably not what you want for general property copying with
type conversion. For that purpose, check out the
copyProperties() method instead.

Parameters:

bean - JavaBean whose properties are being populated

properties - Map keyed by property name, with the
corresponding (String or String[]) value(s) to be set

setProperty

Set the specified property value, performing type conversions as
required to conform to the type of the destination property.

If the property is read only then the method returns
without throwing an exception.

If null is passed into a property expecting a primitive value,
then this will be converted as if it were a null string.

WARNING - The logic of this method is customized
to meet the needs of populate(), and is probably not what
you want for general property copying with type conversion. For that
purpose, check out the copyProperty() method instead.

WARNING - PLEASE do not modify the behavior of this
method without consulting with the Struts developer community. There
are some subtleties to its functionality that are not documented in the
Javadoc description above, yet are vital to the way that Struts utilizes
this method.